WO2004031461A1

WO2004031461A1 - Process and composition for the production of carbon fiber and mats

Info

Publication number: WO2004031461A1
Application number: PCT/JP2003/012261
Authority: WO
Inventors: Masumi Hirata; Hiroshi Sakurai; Toru Sawaki; Tetsuo Ban; Satoru Ohmori; Shunichi Matsumura; Hideaki Nitta
Original assignee: Teijin Limited
Priority date: 2002-09-30
Filing date: 2003-09-25
Publication date: 2004-04-15
Also published as: JPWO2004031461A1; KR20050061495A; KR101031207B1; CN100338280C; DE60332947D1; EP1550747B1; TWI325450B; ATE470735T1; US20060012061A1; EP1550747A1; AU2003272887A1; TW200412380A; EP1550747A4; CN1685095A; JP3971437B2

Abstract

A resin composition comprising 100 parts by weight of a thermoplastic resin, 1 to 150 parts by weight of a carbon- precursor organic compound (A), and 0.001 to 40 parts by weight of a copolymer constituted of polymeric segments (e1) and (e2) which have surface tensions against the thermoplastic resin and the organic compound (A) within specific ranges: and a process for the production of carbon fiber, characterized by producing a molding of a precursor fiber (B) from the composition, stabilizing the carbon-precursor organic compound (A) contained in the precursor fiber (B) to form a stabilized precursor fiber (C), removing the thermoplastic resin contained in the stabilized precursor fiber (C) to form a fibrous carbon precursor (D) free from the thermoplastic resin, and then subjecting the fibrous carbon precursor (D) to carbonization or graphitization.

Description

Description Method and composition for the production of carbon fibers and mats

The present invention relates to methods and compositions for the production of carbon fibers and mats. More specifically, the present invention relates to a method for producing a carbon fiber having a very small fiber diameter, for example, 0.001 to 5 m, and a mat, and a composition used for the production. Background art

Carbon fiber is used as a filler for high-performance composite materials because of its excellent properties such as high strength, high elastic modulus, high conductivity, and light weight. Its applications are not limited to reinforcing fillers for the purpose of improving mechanical strength, but also as conductive resin fillers for electromagnetic wave shielding materials and antistatic materials, taking advantage of the high conductivity provided by carbon materials. Alternatively, it is expected to be used as a filler for electrostatic coatings on resins. It is also expected to be used as a field electron emission material such as a flat display, taking advantage of the characteristics of chemical stability, thermal stability and microstructure as a carbon material.

Conventionally, carbon fibers have been produced by heat-treating a fibrous carbon precursor such as polyacrylonitrile, pitch, or cellulose at a temperature of 100 ° C. or more to carbonize. The carbon fiber formed by this method is generally a continuous fiber having a fiber diameter of 5 to 20 xm, and it is practically impossible to produce a carbon fiber having a smaller fiber diameter. In the latter half of 1980, research on carbon fiber (Vapor Carbon Fiber; hereinafter abbreviated as VGCF) by the vapor phase method was carried out, and it has now been manufactured industrially. As a specific manufacturing method, JP-A-60-27700 discloses that an organic compound such as benzene is used as a raw material, and an organic transition metal compound such as fuecopene is introduced into a high-temperature reactor together with a carrier gas as a catalyst. Japanese Patent Application Laid-Open No. 60-54998 discloses a method of generating VGCF in a floating state. The method and Patent No. 277784334 disclose a method of growing on a reactor wall. VGCF is physically different from conventional carbon fibers because the fiber diameter is small and not continuous, and has a fiber diameter of several hundred nm and a fiber length of several tens of meters. Ultrafine carbon fibers have higher thermal and electrical conductivity and are less susceptible to corrosion, so they are functionally different from conventional carbon fibers, and are expected to have great future potential in a wide range of applications. Have been.

Also, Japanese Patent Application Laid-Open No. 2001-73226 describes a method for producing ultrafine carbon fibers from a composite fiber of phenol tree J5 and polyethylene. Although there is a possibility that ultrafine carbon fibers can be produced relatively inexpensively in comparison with the gas phase method, the phenol resin needs to be wet and requires a long period of time, and it is difficult to form an orientation. However, since it is a non-graphitizable compound, the strength and elastic modulus of the obtained ultrafine carbon fiber cannot be expected. Disclosure of the invention

An object of the present invention is to provide a method for producing carbon fibers.

Another object of the present invention is to provide a method for efficiently and inexpensively producing ultrafine carbon fibers, for example, ultrafine carbon fibers having a fiber diameter of 0.001 to 5 m.

Still another object of the present invention is to provide a method for efficiently and inexpensively producing a carbon fiber having a small number of branching structures, high strength and high elastic modulus.

Still another object of the present invention is to provide a method for efficiently and inexpensively producing a carbon fiber mat made of the above-mentioned carbon fibers, particularly a mat made of ultrafine carbon fibers.

Still another object of the present invention is to provide a composition for producing carbon fiber which is suitably used in the production method of the present invention.

Still another object of the present invention is to provide a particularly preferable use of the carbon fiber obtained by the production method of the present invention.

Still other objects and advantages of the present invention will become apparent from the following description. According to the present invention, the above objects and advantages of the present invention are: (1) 100 parts by weight of thermoplastic resin and at least one kind of thermoplastic carbon precursor selected from the group consisting of pitch, polyacrylonitrile, polyacrylamide, polyimide, polybenzoazole and aramide 1 to 150 parts by weight Forming a precursor fiber or film by spinning or forming a mixture of

(2) subjecting the precursor fiber or film to a stabilization treatment to stabilize the thermoplastic carbon precursor in the precursor fiber or film to form a stabilized precursor fiber or film;

(3) removing the thermoplastic resin from the stabilized precursor fiber or film to form a fibrous carbon precursor; and (4) carbonizing or graphitizing the fibrous carbon precursor to form carbon fibers. This is achieved by a carbon fiber manufacturing method characterized by the following.

According to the present invention, the above objects and advantages of the present invention are:

(1) 100 parts by weight of a thermoplastic resin and at least one kind of thermoplastic carbon precursor selected from the group consisting of pitch, polyacrylonitrile, polypropylimide, polyimide, polybenzazole and aramide 1 to 150 parts by weight Forming a precursor film by melt-extruding a mixture comprising

(2) subjecting the precursor film to a stabilization treatment to stabilize the thermoplastic carbon precursor in the precursor film to form a stabilized precursor film,

(3) A plurality of the stabilized precursor films are laminated to form a stabilized precursor superimposed film,

() Removing the thermoplastic resin from the stabilized precursor superimposed film to form a fibrous carbon precursor mat; and

(5) The carbon fiber mat is formed by carbonizing or graphitizing the fibrous carbon precursor mat.

This is achieved by a method for producing a carbon fiber mat.

According to the present invention, the above object and advantages of the present invention are, thirdly, 100 parts by weight of thermoplastic resin and pitch, acrylonitrile, polycarboimide, polyimide, polybenzoazole, and aramide. At least one type of heat Plastic carbon precursor :! It is achieved by a composition for producing fibrous carbon comprising up to 150 parts by weight.

According to the present invention, fourthly, the above objects and advantages of the present invention are provided by the use of the carbon fiber obtained by the production method of the present invention for use in a battery electrode or in combination with a resin. Is done. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an SE (Μ) photograph of the resin composition of Example 1 (Al 100) (× 10,000).

FIG. 2 shows the distribution of the pitch-dispersed particle diameter of the resin composition of Example 1—A1100).

Figure 3 shows the shear rate dependence of the melt viscosity of ピッチ Ρ and pitch. Preferred embodiments of the invention

Hereinafter, preferred embodiments of the present invention will be described. First, the method for producing carbon fiber will be described.

In step (1), a precursor fiber or film is formed by spinning or forming a mixture comprising 100 parts by weight of a thermoplastic resin and 1 to 150 parts by weight of a thermoplastic carbon precursor.

The thermoplastic resin can be easily removed in step (3) from the stabilized precursor fiber or film produced in step (2). A thermoplastic resin having a weight loss of at least 90% and a weight loss at air temperature of 1,000 ° C of 97% or more is preferably used. Also, since the thermoplastic resin can be easily melt-kneaded and melt-spun with the thermoplastic carbon precursor, when it is crystalline, its crystalline melting point is 100 ° C or more and 400 ° C or less, and it is amorphous. Sometimes the glass transition temperature is preferably from 100 ° C to 250 ° C. When the crystalline melting point of the crystalline resin exceeds 400 ° C., it is necessary to perform the melt kneading at 400 ° C. or higher, which is not preferable because the resin is easily decomposed. In addition, the amorphous resin gas If the lath transition temperature exceeds 250 ° C, handling becomes difficult because the viscosity of the resin during melt-kneading is extremely high, which is not preferable. Further, from another viewpoint, it is preferable that the thermoplastic resin has high gas permeability such as oxygen and halogen gas. For this reason, the thermoplastic resin used in the present invention preferably has a free volume diameter of 0.50 nm or more at 20 ° C evaluated by the positron annihilation method. If the free volume diameter at 20 ° C evaluated by the positron annihilation method is less than 0.50 nm, the gas permeability of oxygen, halogen gas, etc. will decrease, stabilizing the carbon precursor contained in the precursor fiber or film. The time in the step (2) of processing to produce a stabilized precursor fiber or film is extremely long, which is not preferable because the production efficiency is significantly reduced. A more preferable range of the free volume diameter at 20 ° C evaluated by the positron annihilation method is 0.52 nm or more, and more preferably 0.55 nm or more. The upper limit of the diameter of the free volume is not particularly limited, but is preferably as large as possible. The diameter of the free volume, when expressed in a range, is preferably from 0.5 to 1 nm, more preferably from 0.5 to 2 nm.

The thermoplastic resin preferably has a surface tension difference with the thermoplastic carbon precursor of 15 mNZm or less. The mixture in step (1) is formed by blending a thermoplastic resin with a carbon precursor. Therefore, if the surface tension difference with the carbon precursor is larger than 15 mNZm, not only the dispersibility of the carbon precursor in the thermoplastic resin is reduced, but also the problem that the carbon precursor is very easily aggregated is easily caused. The difference in surface tension between the thermoplastic resin and the carbon precursor is more preferably within 1 OmN / m, and particularly preferably within 5 mNZm.

Specific examples of the thermoplastic resin having the above characteristics include, for example, the following formula (I):

Here, RR ² , R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, and an aryl group having 6 to 12 carbon atoms. Or an aralkyl group having 7 to 12 carbon atoms, and n is a number of 20 or more, preferably 20 to 100,000.

The polymer represented by these is mentioned.

Examples of the thermoplastic resin represented by the above formula (I) include polyethylene, amorphous polyolefin, a homopolymer of 4-methylpentene-11, and a copolymer of 4-methylpentene-11 with other olefins, for example, poly-4 And a polymer in which a vinyl monomer is copolymerized with 1-methylpentene-1. Examples of polyethylene include high-pressure low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, and other homopolymers of ethylene or copolymers of ethylene and α-olefin; ethylene-vinyl acetate copolymer. Copolymers of ethylene and other vinyl monomers such as polymers are exemplified. Examples of the α-olefin copolymerized with ethylene include propylene, 1-butene, 11-hexene, and 1-octene. Other vinyl monomers include, for example, vinyl esters such as biel acetate; (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, and η-butyl (meth) acrylate. (Meth) acrylic acid and its alkyl esters.

The thermoplastic carbon precursor used in the present invention is pitch, polyacrylonitrile, polycarboimide, polyimide, polybenzoazole, and aramide. These are susceptible to carbonization and graphitization at temperatures above 1000 ° C. Among these, pitch, polyacrylonitrile, and polyacrylamide are preferable, and pitch is more preferable. In addition, among pitches, a mesophase pitch which is generally expected to have high strength and high elastic modulus is preferable.

Pitch is a mixture of condensed polycyclic aromatic hydrocarbons obtained as a coal or petroleum distillation residue or raw material, and is usually amorphous and optically isotropic (this is generally called isotropic pitch). . When an isotropic pitch having a certain property is heated to 350 to 500 ° C. in an inert gas atmosphere, it passes through various routes and finally exhibits an optically anisotropic nematic phase. Can be converted to a mesophase pitch including a pitch liquid crystal. Mesophase pitch is made from aromatic hydrocarbons such as benzene and naphthylene. Can be manufactured. The mesophase pitch is sometimes called anisotropic pitch or liquid crystal pitch due to its characteristics. As the mesophase pitch, a mesophase pitch using an aromatic hydrocarbon such as naphthalene as a raw material is preferable from the viewpoint of stabilization, carbonization, or ease of graphitization. The above thermoplastic carbon precursors can be used alone or in combination of two or more.

The thermoplastic carbon precursor is used in an amount of 1 to 150 parts by weight, preferably 5 to 100 parts by weight, based on 100 parts by weight of the thermoplastic resin. If the amount of the carbon precursor is more than 150 parts by weight, a precursor fiber or a film having a desired dispersion diameter cannot be obtained, and if the amount is less than 1 part by weight, the intended ultrafine carbon fiber is produced at low cost. It is not preferable because problems such as inability to do so occur.

As a method for producing a mixture of the thermoplastic resin and the carbon precursor organic compound (A), kneading in a molten state is preferred. In particular, melt-kneaded in a range ratio (7 Μ _/? _Α) is 0.5 to 5 0 in the melt viscosity of the melt viscosity (77 _M) and the thermoplastic carbon precursor in the thermoplastic resin at the time of melt kneading (7 _Alpha) Is preferred. If the value of ( _ηΑ ) is less than 0.5 or greater than 50, the dispersibility of the thermoplastic carbon precursor in the thermoplastic shelf will not be good, which is not preferable. The more preferable range of _(7? Μ Ζ τ7 _Α) value is from 0.7 to 5. A known kneading apparatus such as a single-screw extruder, a twin-screw extruder, a mixing roll, and a Banbury mixer can be used for melt-kneading the thermoplastic resin and the thermoplastic carbon precursor. Among them, a coaxial twin-screw extruder is preferably used for the purpose of micro-dispersing the thermoplastic carbon precursor in a good manner in terms of thermoplasticity. The melt-kneading temperature is, for example, 100 ° C. (: up to 400 ° C.) When the melt-kneading temperature is lower than 100 ° C., the thermoplastic carbon precursor does not go into a molten state, but is converted into a thermoplastic resin. On the other hand, if the temperature exceeds 400 ° C., it is not preferable because the decomposition of the thermoplastic resin and the thermoplastic carbon precursor proceeds, and both are not preferable. 150 to 350 ° C. The melt-kneading time is 0.5 to 20 minutes, preferably 1 to 15 minutes.The melt-kneading time is less than 0.5 minute. In such a case, it is not preferable because dispersion of the thermoplastic carbon precursor in the micro-mouth is difficult, while if it exceeds 20 minutes, the productivity of the ultrafine carbon fiber is remarkably reduced. The melt-kneading of the plastic resin and the thermoplastic carbon precursor is preferably performed in an atmosphere having an oxygen gas content of less than 10%. The thermoplastic carbon precursor used in the present invention reacts with oxygen to be denatured and infused during melt-kneading, which may hinder micro-dispersion in the thermoplastic resin. For this reason, it is preferable to carry out melt-kneading while flowing an inert gas to reduce the oxygen gas content as much as possible. More preferably, the oxygen gas content at the time of melt-kneading is less than 5%, more preferably less than 1%.

The mixture of the thermoplastic resin and the thermoplastic carbon precursor can contain a compatibilizer between the thermoplastic resin and the thermoplastic carbon precursor. The compatibilizer is preferably added during the above-mentioned melt-kneading. '

Examples of such a compatibilizer include the following formula (1): Surface tension of polymer segment (el)

0.7 k <1.3

Surface tension of thermoplastic carbon precursor

(1)

Surface tension of the polymer segment (e l) satisfying the following equation and the following formula (2):

0.7 k <1.3

Surface tension of thermoplastic resin

(2)

The surface tension of the copolymer (E) of the polymer segment (e 2) and the following formulas (3) and (4):

0.7 k <1.3

Surface tension of thermoplastic carbon precursor

(3) Surface tension of homopolymer (F)

0.7 <1.3

Surface tension of thermoplastic resin

... ₍₄₎

Polymers selected from the group consisting of homopolymers (F) satisfying the following are preferably used.

The use of the above-mentioned compatibilizer makes it possible to reduce the dispersion particle size and the particle size distribution of the thermoplastic carbon precursor in the thermoplastic resin, so that the finally obtained carbon fiber becomes extremely finer than before and the fiber The diameter distribution also narrows. '

In addition, even when the content of the carbon precursor in the thermoplastic resin is gradually increased, it is possible to prevent the two from immediately contacting and fusing.

The above equation (1) for the copolymer (E) represents the ratio of the surface tension of the thermoplastic carbon precursor to the surface tension of the polymer segment (e l). That is, it shows one parameter of the interfacial energy between the polymer segment (el) and the carbon precursor. If this ratio is smaller than 0.7 or larger than 1.3, the interfacial tension between the polymer segment (el) and the carbon precursor will be high, and the interfacial adhesion between the two phases will not be good. A more preferable range of the ratio of the surface tension of the carbon precursor to the surface tension of the polymer segment (el) is 0.75 to 1.25, and more preferably 0.8 to 1.2. The polymer segment (el) is not particularly limited as long as it satisfies the above formula (1). Examples thereof include polyolefin homopolymers or copolymers such as polyethylene, polypropylene, and polystyrene, polymethacrylates, and polymethyl methacrylate. Polyacrylate homopolymers or copolymers can be preferably used. Further, a styrene copolymer such as acrylonitrile-styrene-coborymer and acrylonitrile-butylene-styrene copolymer may be used. Of these, homopolymers and copolymers of styrene are preferred.

The above equation (2) for the copolymer (E) represents the ratio of the surface tension of the thermoplastic resin to the surface tension of the polymer segment (e 2). In other words, it shows the parameters of the interfacial energy between the polymer segment (e 2) and the thermoplastic resin. this If the ratio is less than 0.7 or greater than 1.3, the interfacial tension between the polymer segment (e 2) and the thermoplastic resin will increase, and the interfacial adhesion between the two phases will not be good. A more preferable range of the ratio of the surface tension of the thermoplastic resin to the surface tension of the polymer segment (e2) is 0.75 to 1.25, and more preferably 0.8 to 1.2. The polymer segment (e2) is not particularly limited as long as it satisfies the above formula (2). For example, polyolefin homopolymers or copolymers such as polyethylene, polypropylene and polystyrene, polymethacrylate, and polymethylmethacrylate Such polyacrylate homopolymers or copolymers can be preferably used. Further, a copolymer such as an acrylonitrile-styrene copolymer or an acrylonitrile-butylene-styrene copolymer may be used. Of these, homopolymers and copolymers of ethylene are preferred.

The above copolymer (E) can be a graft copolymer or a block copolymer. The copolymer composition ratio of the polymer segments (el) and (e2) is in the range of 10 to 90% by weight for the polymer segment (el) and 90 to 90% by weight for the polymer segment (e2). Those are preferably used. Such copolymers of two different polymer segments include, for example, a copolymer of polyethylene and polystyrene, a copolymer of polypropylene and polystyrene, and a copolymer of ethylene-glycidyl methacrylate copolymer and polystyrene. Copolymer, ethylene-ethyl acrylate copolymer and polystyrene copolymer, ethylene-vinyl acetate copolymer and polystyrene copolymer, polyethylene and polymethyl methacrylate copolymer, ethylene-daricidyl methacrylate copolymer Copolymer of polymer and polymethyl methacrylate, copolymer of ethylene-ethyl acrylate copolymer and polymethyl methacrylate, copolymer of ethylene-vinyl acetate copolymer and polymethyl methacrylate, acrylonitrile Copolymerization of Rustyrene Copolymer with Polyethylene Copolymer of acrylonitrile-styrene and polypropylene, copolymer of acrylonitrile-styrene copolymer and ethylene-daricidyl methacrylate copolymer, acrylonitrile-styrene copolymer and ethylene-ethyl acetate Copolymer with acrylate copolymer, copolymer of acrylonitrile styrene copolymer and ethylene monoacetate biel copolymer Copolymers and the like can be mentioned.

Furthermore, the above formula (3) for the above homopolymer (F) can be similarly understood by replacing the polymer segment (el) in the above formula (1) with a homopolymer (F). Can be similarly understood by replacing the polymer segment (e 2) in the above formula (2) with a homopolymer (F). Examples of the homopolymer (F) include polyolefin homopolymers such as polyethylene, polypropylene, and polystyrene, and polyacrylate homopolymers such as polymethacrylate and polymethyl methacrylate.

The amount of the compatibilizer as described above is preferably 0.001 to 40 parts by weight, more preferably 0.001 to 20 parts by weight, based on 100 parts by weight of the thermoplastic resin. In the mixture formed as described above used in the step (1), the dispersion diameter of the carbon precursor in the thermoplastic resin is preferably 0.01 to 50 m. In the mixture, the carbon precursor forms an island phase and becomes spherical or elliptical. As used herein, the term “dispersion diameter” refers to the spherical diameter of the carbon precursor or the major axis diameter of the ellipsoid in the mixture. If the dispersion diameter of the carbon precursor in the thermoplastic resin is outside the range of 0.01 to 50 im, it becomes difficult to produce a carbon fiber filler for high-performance composite materials, which is not preferable. A more preferable range of the dispersion diameter of the carbon precursor is 0.01 to 3. Also, even after the mixture of the thermoplastic resin and the carbon precursor is kept at 300 ° C for 3 minutes, the dispersion diameter of the carbon precursor in the thermoplastic resin is preferably 0.01 to 50 m. preferable. If a mixture obtained by melt-kneading a thermoplastic resin and a carbon precursor is kept in a molten state, the carbon precursor will aggregate with time. If the dispersion diameter exceeds 5 O / ^ m due to the aggregation of the carbon precursor, it becomes difficult to produce a carbon fiber filler for high-performance composite materials, which is not preferable. The degree of the agglomeration rate of the carbon precursor varies depending on the type of the thermoplastic resin and the carbon precursor used, but is more preferably 5 minutes at 300 ° C, more preferably 10 minutes or more at 300 ° C. Preferably, a dispersion diameter of ~ 50 m is maintained.

In the step (1), the mixture is spun to form a precursor fiber or formed into a precursor film. Examples of the method for forming the precursor fiber include a method in which a mixture obtained by melt blending is melt-spun from a spinneret. The spinning temperature during melt spinning is, for example, 100 to 400 ° C., preferably 150 to 400 ° C., and more preferably 180 to 350 ° C. is there. The spinning take-off speed is preferably from 1 Om / min to 2,000 OmZ. Outside the above range, a fibrous molded article (precursor fiber) composed of a desired mixture cannot be obtained, which is not preferable. When the mixture is melt-kneaded and then melt-spun from a spinneret, it is preferable to melt-knead and then send the liquid in the pipe in a molten state and melt-spin from the spinneret. Preferably, the transfer time is within 10 minutes.

The cross-sectional shape of the precursor fiber can be circular or irregular, and its thickness is preferably from 1 to 100 / m in equivalent diameter converted to a circle.

As a method of forming a precursor film, for example, a method in which the mixture is sandwiched between two plates and one of the plates is rotated to create a film to which shear is applied, and a sudden stress is applied to the mixture by a compression press machine. In addition, a method of producing a film to which a shear is applied, a method of producing a film to which a shear is applied by a rotating roller, and the like can be given. The shear is, for example, in the range of ^{1 to 100} , 0000 S1. The precursor film can be formed by melt-extruding the mixture through a slit. The melt extrusion temperature is preferably between 100 and 400 ° C.

Further, by stretching a fibrous or film-like molded body in a molten state or a softened state, a precursor fiber or a precursor film in which a carbon precursor is elongated may be produced. These treatments are preferably performed at 150 ° C. to 400 ° C., more preferably at 180 ° C. (: to 350 ° C.).

The thickness of the precursor film is preferably from 1 to 500 m. If the thickness is more than 500 m, in the next step (2) of contacting the precursor film with a gas containing oxygen and / or iodine gas to obtain a stabilized precursor film, the gas permeability is significantly reduced. Therefore, it takes a long time to obtain a stabilized precursor film as a result, which is not preferable. On the other hand, if it is less than 1 m, it is not preferable because handling of the precursor film is difficult. Now, according to the present invention, as described above with respect to the step (1), 100 parts by weight of the thermoplastic resin and at least one kind selected from the group consisting of pitch, acrylonitrile, polycarboimide, polyimide, polybenzoazole and aramide There is provided a composition for producing fibrous carbon, comprising 1 to 150 parts by weight of a thermoplastic carbon precursor. The above composition comprises a copolymer (E) of a polymer segment (e 1) satisfying the above formula (1) and a polymer segment (e 2) satisfying the above formula (2), and the above formula (3) One or more homopolymers (F) satisfying (4) may further contain 0.001 to 20 parts by weight.

These compositions may consist essentially of 100 parts by weight of the thermoplastic resin and 1-150 parts by weight of the thermoplastic carbon precursor, or may be composed of them and the copolymer (E) and Z or homopolymer. Polymer (F) can consist essentially of 0.01 to 20 parts by weight.

Also, these compositions are preferably

(i) The thermoplastic carbon precursor is dispersed in a granular form in the thermoplastic resin matrix, and the average equivalent particle size of the dispersed thermoplastic carbon precursor is in the range of 0.01 to 50 m. , Or

(ii) after holding at 300 for 3 minutes, the average equivalent particle size of the dispersed thermoplastic carbon precursor is in the range of 0.01 to 50 m, or

(iii) shear rate 1, 0 0 0 0 The melt viscosity of the thermoplastic resin melt viscosity of the thermoplastic carbon precursor in S ^1. 5 to 3 Thermoplastic resin 0 times become such temperatures and the thermoplastic carbon It is prepared by mixing precursors.

Next, in the step (2) of the present invention, the precursor fiber or the film is subjected to a stabilization treatment to stabilize the thermoplastic carbon precursor in the precursor fiber or the film, thereby forming the stabilized precursor fiber or the film. Form.

The stabilization of the thermoplastic carbon precursor is a necessary step to obtain carbonized or graphitized ultrafine carbon fibers.If the thermoplastic resin and copolymer are removed without performing this step However, problems such as the thermal decomposition and fusion of the thermoplastic carbon precursor occur. Stabilization methods include, for example, gas flow treatment with oxygen, acidic aqueous solution And known methods such as solution treatment. From the viewpoint of productivity, stabilization (infusibility) by gas stream treatment is preferable. The gas component used is selected from the viewpoints of the permeability into the thermoplastic resin and the adsorption to the thermoplastic carbon precursor, and the capability of rapidly infusing the thermoplastic carbon precursor at a low temperature. It is preferably a mixed gas containing oxygen and Z or a halogen gas. Examples of the halogen gas include fluorine gas, chlorine gas, bromine gas, and iodine gas. Among them, bromine gas and iodine gas are particularly preferable. As a specific method of infusibility under a gas stream, preferably 50 to 350 ° (: more preferably at 80 to 300 ° C, for 5 hours or less, preferably 2 hours The treatment is performed in a desired gas atmosphere, and the softening point of the thermoplastic carbon precursor contained in the precursor fiber or the film is significantly increased by the infusibilization, but is softened for the purpose of obtaining a desired ultrafine carbon fiber. The temperature is preferably at least 400 ° C., and more preferably at least 500 ° C. Next, in the step (3) of the present invention, the heat can be removed from the stabilized precursor fiber or film. Removal of the plastic resin to form a fibrous carbon precursor Removal of the thermoplastic resin is achieved by thermal decomposition or dissolution in a solvent, and which method is used depends on the thermoplastic resin used. Depends on the thermoplastic used. In the gas atmosphere, a temperature of 400 to 600 ° C., more preferably 500 to 600 ° C. is used, and the gas atmosphere is, for example, an inert gas such as argon or nitrogen. Alternatively, an oxidizing gas atmosphere containing oxygen may be used, and a solvent having a higher solubility may be used for dissolution in a solvent, depending on the thermoplastic resin used, for example, methylene chloride in polycarbonate. Petrahydrofuran is preferred, and for polyethylene, decalin and toluene are preferred.

Finally, in step (4) of the present invention, the fibrous carbon precursor is carbonized or graphitized to form carbon fibers. The carbonization or graphitization of the fibrous carbon precursor can be performed by a method known per se. For example, a fibrous carbon precursor is subjected to high temperature treatment in an inert gas atmosphere to be carbonized or graphitized. The inert gas used includes nitrogen, argon and the like, and the temperature is preferably 500 to 3,500 ° C, more preferably 700,000 to 3,000 ° C, Particularly preferably 800 ° C ~ 3, 0000 ° C It is. The oxygen concentration during carbonization or graphitization is preferably 20 ppm or less, more preferably 1 O ppm or less. The fiber diameter of the obtained ultrafine carbon fiber is preferably 0.001 zm to 5 m, and more preferably 0.001 m! ~ Lm.

By performing the above method, it is possible to produce carbon fibers having a small number of branch structures and high strength and high elastic modulus.

By the above method, for example, ultrafine carbon fibers having a fiber diameter of 0.001 m to 5 m can be obtained. The ultrafine carbon fiber obtained from the composite fiber of the phenol resin and the polyethylene was amorphous because the phenol resin was amorphous, so that the obtained ultrafine carbon fiber was also amorphous, and both the strength and the modulus were low. However, the carbon fibers obtained by this method have extremely strong molecular chains in the direction of the fiber axis, and have low strength and high elastic modulus as compared with ultrafine carbon fibers obtained from a composite fiber of phenol resin and polyethylene. In addition, since the branched structure is smaller than the carbon fiber obtained by the gas phase method, it is possible to reinforce a polymer or the like by adding a smaller amount than before.

According to the present invention, there is further provided a method for producing a carbon fiber mat as an aggregate of carbon fibers instead of independent carbon fibers by further developing the above method of the present invention. That is, the method for producing a carbon fiber mat of the present invention comprises:

(1) 100 parts by weight of thermoplastic resin and at least one kind of thermoplastic carbon precursor selected from the group consisting of pitch, polyacrylonitrile, polyphenolimide, polyimide, polybenzoazole and aramide A mixture consisting of parts by weight is formed by melt extrusion to form a precursor film,

(4) removing the thermoplastic resin from the stabilized precursor superimposed film to form a fibrous carbon precursor mat, and

(5) Carbon fiber mat is formed by carbonizing or graphitizing the fibrous carbon precursor mat. Make,

Consisting of

The above step (1) is the same as the method for producing a precursor film in step (1) of the method for producing carbon fibers.

Step (2) is the same as the method for producing the stabilized precursor film in step (2) of the method for producing carbon fiber.

In the step (3), a plurality of, for example, 2 to 100,000 stabilized precursor films obtained in the step (2) are superposed to form a superimposed stabilized precursor film.

Step (4) removes the thermoplastic resin from the stabilized superimposed film to form a fibrous carbon precursor mat. This step (4) can be performed by removing the thermoplastic resin in the same manner as in step (3) of the carbon fiber production method.

In step (5), the fibrous carbon precursor mat is carbonized or graphitized to form a carbon fiber mat. The carbonization and graphitization in this step (5) can be carried out in the same manner as in step (4) of the carbon fiber production method.

According to the method of the present invention, a carbon fiber mat made of ultrafine carbon fibers can be produced very easily. Such a carbon fiber mat is very useful, for example, as a high-performance filter or a battery electrode material. Example

Hereinafter, examples of the present invention will be described. The present invention is not limited by the contents described below.

The dispersed particle diameter of the thermoplastic carbon precursor in the thermoplastic resin and the fiber diameter of the precursor fiber were measured with a scanning electron microscope S-2400 (Hitachi, Ltd.). The strength and elastic modulus of the obtained carbon fiber were measured using Tensilon RTC-1225A (A & D / Oriental Tech). The surface tensions of the polymer segment (e 1), the polymer segment (e 2), the thermoplastic carbon precursor and the thermoplastic resin are as defined in JISK 668 “Plastic film and sheet”. The test was performed using the reagents used in the "Test Method for Wetting Tension". The diameter of the free volume of thermoplastic resin is Using ²² Na ₂ C0 _3, the long-lived components of the positron lifetime spectra were evaluated by using El spherical model equation given pore size to (Ch em. Phy s. 63 , 51 (1981)). The melting point or glass transition temperature of the thermoplastic resin was measured using a DSC 2920 (manufactured by TA Instruments) at a heating rate of 10 ° C./min.

The soft point was measured by a trace melting point measuring device. The melt viscosity (77 M) of the thermoplastic resin and the melt viscosity (7) of the thermoplastic carbon precursor at the shear rate during melt-kneading were evaluated from the shear rate dependence of the melt viscosity (Fig. 3). The shear rate (SR) during melt-kneading was evaluated using the following equation (3).

(SR) = [2πDZ (η / 60)] C (3)

Here, D indicates the screw outer diameter (m), n indicates the screw rotation speed (rpm), and C indicates the clearance (m).

Example 1

100 parts by weight of high density polyethylene (manufactured by Sumitomo Chemical Co., Ltd.) as a thermoplastic resin and 11.1 parts of mesophase pitch AR—HP (manufactured by Mitsubishi Gas Chemical Company) as a thermoplastic carbon precursor, and Modiper A 1100 (manufactured by NOF Corporation: 0.56 parts of a low-density polyethylene 7 Owt% and polystyrene 3 Owt% graft copolymer were melt-kneaded in a coaxial twin-screw extruder (Nippon Steel Works TEX-30, barrel temperature 290 ° C, under nitrogen flow). Thus, a resin mixture was prepared. The shear rate (SR) generated in the resin mixture during melt-kneading was 628 s- ¹ . At this shear rate, the ratio of the melt viscosity (7 樹脂_M ) of the thermoplastic resin to the melt viscosity (7? _A ) of the thermoplastic carbon precursor (7) _Μ ΖΤ _Α ) was 1.2. The dispersion diameter of the thermoplastic carbon precursor obtained under these conditions in the thermoplastic resin was 0.05 to 2 xm (see Fig. 1). When the particle size distribution of AR-HP was evaluated using a scanning electron microscope, the particle size of less than 1 m accounted for 90% or more (see Fig. 2). The resin composition was kept at 300 ° C. for 10 minutes, but no aggregation of the thermoplastic carbon precursor was observed, and the dispersion diameter was 0.05 to 2 m. The surface tensions of high-density polyethylene (Sumitomo Chemical Co., Ltd.), low-density polyethylene (Sumitomo Chemical Co., Ltd.), mesophase pitch, and polystyrene are 31, 31, 22, and 24 mNZm, respectively. The value (surface tension of the polymer segment (el) Z surface tension of the thermoplastic carbon precursor) is 1.1, and the value of (the surface tension of the polymer segment (e 2) Z surface tension of the thermoplastic resin) is 1.0. Met.

The above resin mixture was spun from a spinneret at 300 ° C to prepare a precursor fiber (composite fiber). The fiber diameter of this composite fiber was 20 m, and the dispersion diameter of the mesophase pitch in the cross section was all 2 m or less. Next, 100 parts by weight of this composite fiber and 5 parts by weight of iodine were placed in a pressure-resistant glass container and kept at 100 ° C. for 10 hours to obtain a stabilized precursor fiber. The temperature of the stabilized precursor fiber was gradually raised to 500 ° C. to remove high-density polyethylene and Modiper A 1100. Thereafter, the temperature was raised to 1,500 ° C in a nitrogen atmosphere and maintained for 30 minutes to perform carbonization. The fiber diameter of the obtained ultrafine carbon fiber was in the range of 0.01 m to 2 m, and almost no branched structure was observed. When the strength and elastic modulus of the ultrafine carbon fiber having a fiber diameter of 1 m were measured, the tensile strength was 2,500 MPa and the tensile elastic modulus was 300 GPa.

Example 2

100 parts by weight of high density polyethylene (manufactured by Sumitomo Chemical Co., Ltd.) as a thermoplastic resin and Mesophase Pitch AR—HP (manufactured by Mitsubishi Gas Chemical Company) 66.7 parts as a thermoplastic carbon precursor, and Modipa A 1100 (manufactured by NOF Corporation) : Graft copolymer of 7 Owt% of low-density polyethylene and 3 Owt% of polystyrene) 0.56 parts are melt-kneaded in a co-axial twin screw extruder (Nippon Steel Works TEX-30, barrel temperature 290 ° C, under nitrogen flow) Thus, a resin mixture was prepared. The shear rate (SR) generated in the resin mixture during melt-kneading is

628 s— ^one . The ratio of the melt viscosity (77 _M) and the melt viscosity of the thermoplastic carbon precursor in the thermoplastic resin in the shear rate _{_{(77 A) (τ? Μ}} / τ7 Α) 1. was 2. The dispersion diameter of the thermoplastic carbon precursor obtained under these conditions in the thermoplastic resin was 0.05 to 22 m. When the particle size distribution of A-HP was evaluated with a scanning electron microscope, the particle size of less than 1 zm accounted for 90% or more. The resin mixture was kept at 300 ° C. for 10 minutes, but no aggregation of the thermoplastic carbon precursor was observed, and the dispersion diameter was 0.05 to 2 wm. The surface tension of high-density polyethylene (Sumitomo Chemical Co., Ltd.), low-density polyethylene (Sumitomo Chemical Co., Ltd.), mesophase pitch, and polystyrene Are 31, 31, 22, and 24 mN "m, respectively. The surface tension of the polymer segment (el) Z surface tension of the thermoplastic carbon precursor is 1.1, and the surface tension of the polymer segment (e 2) is 1.1. The surface tension of the Z thermoplastic resin) was 1.0.

The above resin mixture was spun from a spinneret at 300 ° C to prepare a precursor fiber (composite fiber). The fiber diameter of this composite fiber was 20 m, and the dispersion diameter of the mesophase pitch in the cross section was all 2 m or less. Next, 100 parts by weight of the composite fiber and 5 parts by weight of iodine were placed in a pressure-resistant glass container and kept at 100 ° C. for 10 hours to obtain a stabilized precursor fiber. The temperature of the stabilized precursor fiber was gradually raised to 500 ° C to remove high-density polyethylene and Modiper A 1100. Thereafter, in a nitrogen atmosphere, the temperature was raised to 1,500 ° C., and the temperature was maintained for 30 minutes to perform carbon shading. The fiber diameter of the obtained ultrafine carbon fiber was in the range of 0.01 m to 2 m, and almost no branched structure was observed. When the strength and elastic modulus of the ultrafine carbon fiber having a fiber diameter of 1 zm were measured, the tensile strength was 2,500 MPa and the tensile elastic modulus was 300 GPa.

Example 3

Poly-1-methylpentene-1 (TPX: Grade RT-18 [Mitsui Chemicals]) 100 parts by weight as a thermoplastic resin and Mesophase Pitch AR-HP (Mitsubishi Gas Chemicals) as a thermoplastic carbon precursor 11.1 The resin mixture was melt-kneaded in a twin-screw extruder (TEX-30, Japan Steel Works, barrel temperature 290 ° C, under a nitrogen stream) to form a resin mixture. The dispersion diameter of the thermoplastic carbon precursor obtained under these conditions in the thermoplastic resin was 0.05 to 2 m. The resin mixture was kept at 300 ° C for 3 minutes, but no agglomeration of the thermoplastic carbon precursor was observed, and the dispersion diameter was 0.05 to 2 ^ m. The surface tensions of poly-14-methylpentene-11 and mesophase pitch were 24 and 22 mN / m, respectively. The average diameter of the free volume of poly (4-methylpentene) -11 evaluated by the positron annihilation method was 0.64 nm, and the melting point of the crystal evaluated by DSC was 238 ° C.

The above resin mixture was spun from a spinneret at 300 ° C to prepare a precursor fiber (composite fiber). The fiber diameter of this composite fiber was 20 m, and the dispersion diameter of the mesophase pitch in the cross section was all 2 m or less. Next, 100 parts by weight of this composite fiber And 10 parts by weight of iodine were placed in a pressure-resistant glass container and kept at 190 ° C for 2 hours to obtain a stabilized precursor fiber. The temperature of the stabilized precursor fiber was gradually raised to 500 ° C. to remove poly-4-methylpentene-1. Thereafter, the temperature was raised to 1,500 ° C in a nitrogen atmosphere and maintained for 30 minutes to perform carbonization. The fiber diameter of the obtained ultrafine carbon fiber was in the range of 0.01 to 2 m, and almost no branched structure was observed. When the strength and elastic modulus of the ultrafine carbon fiber having a fiber diameter of 1 m were measured, the tensile strength was 2,500 MPa and the tensile elastic modulus was 30 OGPa.

Example 4

100 parts by weight of high-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd.) as a thermoplastic resin and mesophase pitch AR—HP (manufactured by Mitsubishi Gas Chemical Company) as a thermoplastic carbon precursor 11. 1 part of a twin-screw extruder (Nippon Steel Works TEX) — 30, LZD = 42, barrel temperature 290 ° C, under a nitrogen stream) to form a resin mixture. The dispersion diameter of the thermoplastic carbon precursor in the thermoplastic resin was 0.1 to: L 0 m. The resin mixture was kept at 300 ° C for 10 minutes, but no agglomeration of the thermoplastic carbon precursor was observed, and the dispersion diameter was 0.1 to 10 m. The above resin mixture was sandwiched between quartz plates heated to 300 ° C using a heating shear flow observation device (CS-450A manufactured by Japan High-Tech Co., Ltd.) and subjected to 750 s- ¹ shear for 1 minute. The film was rapidly cooled to room temperature to form a film having a thickness of 6 Oim. When the thermoplastic carbon precursor contained in the film was observed using the above equipment, it was confirmed that fibers with a fiber diameter of 0.01 to 5 / im and a fiber length of 1 to 20 mm were generated. Was done. Next, 100 parts by weight of this film and 5 parts by weight of iodine were placed in a pressure-resistant glass container and kept at 100 ° C. for 10 hours to obtain a stabilized precursor film. The temperature of the stable drier precursor film was gradually raised to 500 ° C. to remove high-density polyethylene. Then, the temperature was raised to 1,500 ° C in a nitrogen atmosphere and maintained for 30 minutes to carbonize AR-HP. The fiber diameter of the obtained ultrafine carbon fiber was in the range of 0.01 m to 5 m, and almost no branched structure was observed.

Example 5

100 parts by weight of high-density polyethylene (Sumitomo Chemical Co., Ltd.) as a thermoplastic resin and mesophase pitch AR—HP (Mitsubishi Gas Chemical Co., Ltd.) as a thermoplastic carbon precursor 11. One part was melt-blended with a twin-screw extruder (Nippon Steel Works TEX-30, LZD = 42, barrel temperature 290 ° under a nitrogen stream) to prepare a resin mixture. The dispersion diameter of the thermoplastic carbon precursor in the thermoplastic resin was 0.1 to 10 m. Further, the resin mixture was kept at 300 ° C for 10 minutes, but no aggregation of the thermoplastic carbon precursor was observed, and the dispersion diameter was 0.1 to 10 xm. The melt viscosity of the thermoplastic resin at 300 ° C and a shear rate of 1,000 s- ¹ was 10 times that of the mesophase pitch AR-HP. The above resin mixture was spun from a spinneret at 300 ° C to prepare a precursor fiber (composite fiber). The fiber diameter of this composite fiber was 20 xm, and the dispersion diameter of AR-HP in the cross section was all less than 10 m. Next, 100 parts by weight of this composite fiber and 5 parts by weight of iodine were placed in a pressure-resistant glass container and kept at 100 ° C. for 10 hours to obtain a stabilized precursor fiber. The temperature of the stabilized precursor fiber was gradually raised to 500 ° C to remove high-density polyethylene. Thereafter, the temperature was raised to 1,500 ° C in a nitrogen atmosphere and maintained for 30 minutes to carbonize the AR-HP. The fiber diameter of the obtained ultrafine carbon fiber was in the range of 0.01 zm to 5 m, and almost no branched structure was observed. When the strength and elastic modulus of the ultrafine carbon fiber having a fiber diameter of I / m were measured, the tensile strength was 2,500 MPa and the tensile elastic modulus was 300 GPa.

Example 6

100 parts by weight of high density polyethylene (manufactured by Sumitomo Chemical Co., Ltd.) as a thermoplastic resin and 10 parts by weight of mesophase pitch AR—HP (manufactured by Mitsubishi Gas Chemical Company) as a thermoplastic carbon precursor are twin-screw extruders (Nippon Steel Works TEX— 30, L / D = 42, barrel temperature 290 ° C, under a nitrogen stream), melt-kneaded, fed with a gear pump in a molten state, and spun from a spinneret to obtain a precursor fiber. The fiber diameter of the precursor fiber was 20 m, and the dispersion diameter of A R—HP in the cross section was all less than 10 / m.

100 parts by weight of this precursor fiber and 5 parts by weight of iodine were placed in a pressure-resistant glass container and kept at 100 ° C. for 10 hours. The high-density polyethylene contained in the obtained stabilized precursor fiber was subjected to solvent removal with hot toluene, and the softening point of AR-HP was determined to be 500 ° C or higher.

The temperature of the stabilized precursor fiber is gradually raised to 500 ° C to remove the high-density polyethylene. I left. Then, the temperature was raised to 1,500 ° C in a nitrogen atmosphere and maintained for 30 minutes to carbonize AR-HP. The fiber diameter of the obtained ultrafine carbon fiber was in the range of 0.01 / zm to 5 m, and the carbon fiber intended for the present invention could be obtained. The strength and elastic modulus of the ultrafine carbon fiber with a fiber diameter of 1 m were measured. Table 1 shows the results.

Comparative Example 1 100 parts by weight of a phenolic resin was used as a thermoplastic carbon precursor, and 100 parts by weight of a high-density polyethylene were melt-kneaded with a twin-screw extruder and fed in a molten state by a gear pump to spin a spinneret. Spinning was performed to obtain a precursor fiber. The obtained precursor fiber was immersed in a hydrochloric acid-formaldehyde aqueous solution (hydrochloric acid 18 wt%, formaldehyde 10 wt%) to obtain a stabilized precursor fiber. Next, carbonization was performed in a nitrogen stream at 600 ° C for 10 minutes, and the polyethylene was removed to obtain phenolic ultrafine carbon fibers. The strength and elastic modulus of the ultrafine carbon fiber having a fiber diameter of 1 m were measured. Table 1 shows the results. Comparative Example 2

AR-HP alone was spun in the same manner as in the spinning method for obtaining the precursor fiber in Example 6, to obtain a fiber comprising only AR-HP.

This was subjected to stabilization and graphitization under the same conditions as in Example 6 to obtain carbon fibers having a fiber diameter of 15. Table 1 shows the results.

table 1

Fiber diameter Tensile strength Tensile modulus

(m) (MPa) (GPa) Example 6 1 2500 300 Comparative Example 1 1 700 25 Comparative Example 2 15 2000 200

Claims

Scope of Claim 1. (1) 100 parts by weight of a thermoplastic resin and at least one thermoplastic carbon precursor selected from the group consisting of pitch, polyacrylonitrile, polycarbonate, polyimide, polybenzoazole and aramide 1-150 By spinning or forming a mixture consisting of parts by weight to form a precursor fiber or film;

(2) subjecting the precursor fiber or film to a stabilization treatment to stabilize the precursor fiber or the thermoplastic carbon precursor in the film to form a stabilized precursor fiber or film;

· (3) removing the thermoplastic resin from the stabilized precursor fiber or film to form a fibrous carbon precursor; and

(4) A method for producing carbon fiber, comprising forming a carbon fiber by carbonizing or graphitizing a fibrous carbon precursor. 2. The method according to claim 1, wherein the thermoplastic resin has a free volume diameter of 0.5 nm or more at 20 ° C measured by a positron annihilation method.

3. The thermoplastic resin has the following formula (I)

Here, R ¹ R ² , R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, and an aryl group having 6 to 12 carbon atoms. Or the aralkyl group having 7 to 12 carbon atoms, and n is a number of 20 or more.

4. The method according to claim 1, wherein the thermoplastic resin is at least one selected from the group consisting of homopolymers and copolymers of 4-methylpentene-11 and homopolymers and copolymers of ethylene.

5. The method according to claim 1, wherein the pitch of the thermoplastic carbon precursor is a mesophase pitch.

6. The method according to claim 1, wherein the difference between the surface tension of the thermoplastic resin and the surface tension of the thermoplastic carbon precursor is 15 mNZm or less.

7. The method according to claim 1, wherein the average equivalent diameter of the thermoplastic carbon precursor in the cross section of the precursor fiber or film is in the range of 0.01 to 50; m.

8. The mixture in step (1) is obtained by the following formulas (1) and (2): Surface tension of polymer segment (el)

0.7 <<1.3

Surface tension of thermoplastic carbon precursor

• · · (1)

And the surface tension of the polymer segment (e 2) satisfying the following formula (2):

0.7 7 1.3

Surface tension of thermoplastic resin

… (2)

The copolymer (E) of the polymer segment (e 2) satisfying the following conditions and the following formulas (3) and (4): Surface tension of homopolymer (F)

0.7 k <1.3

Surface tension of thermoplastic carbon precursor

… (3) Surface tension of homopolymer (F)

0.7 × 1.3

Surface tension of thermoplastic resin

…(Four)

The method according to claim 1, further comprising 0.0001 to 20 parts by weight of a polymer selected from the group consisting of homopolymers (F) satisfying the following.

9. The method according to claim 8, wherein the polymer segment (el) is a homopolymer or copolymer of styrene.

10. The method according to claim 8, wherein the polymer segment (e2) is a homopolymer or copolymer of ethylene.

11. The method according to claim 8, wherein the copolymer (E) is a graft copolymer or a block copolymer.

12. The method according to claim 1, wherein the spinning and film formation in the step (1) are performed by melt extrusion.

13. The method according to claim 12, wherein the melt extrusion is performed at a temperature in the range of 100 to 400 ° C.

14. The method according to claim 12, wherein the film is formed by applying a shear force in the range of 1 to 100,000 S- ¹ .

15. The method according to claim 1, wherein in step (1), a precursor fiber having an equivalent diameter of 1 to: 100 m or a precursor film having a thickness of 0.1 to 500 m is formed.

16. The method according to claim 1, wherein the stabilizing treatment in step (2) is performed by bringing the precursor fiber or film into contact with a gas containing oxygen and / or a halogen gas.

17. The method according to claim 1, wherein the precursor fiber or film is drawn between step (1) and step (2). ·

18. The method according to claim 1, wherein the removal of the thermoplastic resin in the step (3) is performed by thermally decomposing and gasifying the thermoplastic resin at a temperature in a range of 400 to 600 ° C.

19. The method according to claim 1, wherein the carbonization or graphitizing in step (4) is performed in an inert atmosphere at a temperature in the range of 700 to 3,000 ° C.

20. (1) 100 parts by weight of thermoplastic resin and at least one kind of thermoplastic carbon precursor selected from the group consisting of pitch, polyacrylonitrile, polycarboimide, polyimide, polybenzoazole and aramide 1 to 150 parts by weight The precursor mixture is formed by melt-extrusion of the resulting mixture to form a precursor film,

(3) stacking a plurality of stabilized precursor films to form a stabilized precursor superimposed film,

(4) removing the thermoplastic shelf from the stabilized precursor superimposed film to form a fibrous carbon precursor mat, and

(5) carbonizing or graphitizing the fibrous carbon precursor mat to form a carbon fiber mat; A method for producing a carbon fiber mat.

21. For the production of fibrous carbon comprising 100 parts by weight of a thermoplastic resin and 1 to 150 parts by weight of at least one thermoplastic carbon precursor selected from the group consisting of pitch, acrylonitrile, polycarbodiimide, polyimide, polybenzoazole and aramide Composition.

22. The following formula (1): Surface tension of polymer segment (e l)

0.7 7 1.3

Surface tension of thermoplastic carbon precursor

... Surface tension of polymer segment (e l) satisfying (1) and the following formula (2): polymer segment (e 2)

0.7 <1.3

Surface tension of thermoplastic resin

· · · (2)

0.7 <1.3

Surface tension of thermoplastic carbon precursor

… (3) Surface tension of homopolymer (F)

0.7 k <1.3

Surface tension of thermoplastic resin

…(Four)

22. The composition according to claim 21, further comprising 0.0001 to 20 parts by weight of a polymer selected from the group consisting of homopolymers (F) satisfying the following.

23. It consists essentially of 100 parts by weight of the thermoplastic resin and 1 to 150 parts by weight of the thermoplastic carbon precursor, or consists of them and the copolymer (E) and / or the homopolymer (F) 0.001 to 20. 23. The composition according to claim 21 or 22 consisting essentially of parts by weight.

24. The thermoplastic carbon precursor is dispersed in a granular form in a thermoplastic resin matrix, and the average equivalent particle size of the dispersed thermoplastic carbon precursor is in the range of 0.01 to 50 m. A composition according to claim 1.

25. The composition according to claim 21, wherein after holding at 300 ° C for 3 minutes, the dispersed thermoplastic carbon precursor has an average equivalent particle size in the range of 0.01 to 50 m.

26. mixing a thermoplastic resin and Netsuka plastic carbon precursor at shear rate 1, in 000 S ¹ melt viscosity of the thermoplastic resin is 0.5 to 30 times the melt viscosity of the thermoplastic carbon precursor such temperatures 22. The composition of claim 21 prepared by:

27. Use of the carbon fiber obtained by the method according to claim 1 for an electrode for a battery.

28. Use for blending with the carbon fiber resin obtained by the method of claim 1 for use.

29. Use of the composition of claim 21 as a raw material for producing carbon fibers.